1. Field of the Invention
The present invention is related to an antenna device and a system, in particular to the antenna device with continuous bending structure, making it easy to tune its radiation field intensity, and its application system.
2. Description of Related Art
In the modern telecommunication technology, many thin and small-sized antennas have been developed for applications in various handy electronic devices. For example, a planar inverted-F (PIFA) antenna is an ordinary type to be mounted on an inner wall of the electronic device when the device is required to be thinner and have better performance. According to the conventional technology, a co-axial cable is provided to couple to a signal feeding point and a signal grounding point of PIFA using an inner conductor and an outer conductor respectively. PIFA then radiates the electromagnetic wave.
However, the conventional kinds of the antennas may not easily be adapted to other devices when they are designed for the proprietary applications. For example, the antenna may be required to have longer shape or size for complying with specific frequency of operation, or the difference between the long side and short side of the antenna may be too large to fit in many devices. Further, in some applications, the conventional antenna needs to occupy a larger space. In other words, the conventional planar inverted-F antenna with a longer side and a shorter side is not easily disposed to devices with limited space for the antenna when it is required to adjust its position and angle within such devices. Furthermore, it is hard to optimize the radiation field by adjusting the position and angle of the antenna when the antenna is mounted within the device.